Noise within an open space is problematic for people working within the open space. Open space noise is typically described by workers as unpleasant and uncomfortable. Speech noise, printer noise, telephone ringer noise, and other distracting sounds increase discomfort. This discomfort can be measured using subjective questionnaires as well as objective measures, such as cortisol levels.
For example, many office buildings utilize a large open office area in which many employees work in cubicles with low cubicle walls or at workstations without any acoustical barriers. Open space noise, and in particular speech noise, is the top complaint of office workers about their offices. One reason for this is that speech enters readily into the brain's working memory and is therefore highly distracting. Even speech at very low levels can be highly distracting when ambient noise levels are low (as in the case of someone having a conversation in a library). Productivity losses due to speech noise have been shown in peer-reviewed laboratory studies to be as high as 41%. Office acoustic design has gotten very good at reducing ambient noise, but the quiet environments that have been created can cause speech noise to contrast strongly with the quiet. Even quiet offices, therefore, can create a level of speech intelligibility that is highly distracting.
Another major issue with open offices relates to speech privacy. Workers in open offices often feel that their telephone calls or in-person conversations can be overheard. Speech privacy correlates directly to intelligibility. Lack of speech privacy creates measurable increases in stress and dissatisfaction among workers.
In the prior art, noise-absorbing ceiling tiles, carpeting, screens, and furniture have been used to decrease office noise levels. Reducing the noise levels does not, however, directly solve the problems associated with the intelligibility of speech. Speech intelligibility can be unaffected, or even increased, by these noise reduction measures. As office densification accelerates, problems caused by open space noise become accentuated.
As a result, improved methods and apparatuses for addressing open space noise are needed.